Steam-boiler and furnace



f UNITED STATES- ATnNrf OFFICE. v

WILLIAM U. FAIRBAIRN, OF HYDE PARK, MASSACHUSETTS.

STEAM-BOILER ANDV FURNACE.

SPECIFICATION forming part of Letters Patent No. 291,041, dated January 1, 1884.

i E Application filed November 20vl 1882. (No model.)

To @ZZ whom it may concern:

Be it known that I, WILLIAM U. FAIR- BAIRN, of Hyde Park, inthe county of Norfolk and State of Massachusetts, have invented a certain new and useful Improvement in Steam-Boilers and Furnaces, of whichthe following is a full, clear, and lexact description, reference being had to the accompanying drawings, forming a part of this specification, in explaining its nature, in which- Figure 1 represents in side elevation asteamboiler, and in vertical section a furnace, containing `my invention. Fig. v2 is a vertical cross-section on the line x of Fig. l.

The ob]l ect of the invention is to provide the boiler` with increased water-heating surface, and to obtain increased combustion. The first I accomplish by arranging the cross-pipe A upon or near the bridge or rear wall of the furnace, and, extending across the combustionchamber diagonally upward therefrom ,a series of small tubes, a, which connect with another cross-pipe, a', parallel with the pipe A. The pipes b b connect the cross pipe a. with the boiler, and the pipe A is also connected with the boiler by means of thepipe b2, the entrance to the boiler from the pipesb b being higher than the point at which the pipe b2 connects with the boiler, for the purpose of obtaining circulation through the pipes and tubes. The tubes a', it willbe observed, extend across the combustion-chamber to very near its front end, and may be arranged in any desired form. For the purpose of directing the products of combustion to the extreme front end of the boiler, the tubes may be embedded or covered, in whole or in part, with re brick or clay, c. To pro- I vide the iire with aproper supply of air,when

this construction is employed, it `will be necessary to supply the combustion-chamber with air let in at the rearof the ash-pit, and for this purpose there is extended through the ash-pit from its front the air-chamber or supply-passage d, which may be of cast-iron, and which may have openings near the bridge-wall, .or extend into the bridge-wall upwardly and ref turn, as represented in Fig. 1, to the front of the bridge-wall, and open into the ash-pit chamber at that point, whereby the opening is protected from ashes, &c.

It will be observed that by this construction the pipes b b bl and A, and especially the tubes a and the cross-pipe a', provide-a very large heating-surface, and that by connecting this system of pipes and tubes with the boiler, as described, provision is made for a circulation of water through them.

It will also be observed that by protecting the tubes, in whole or in part, with fire-clay or fire-brick, a wall or barrier, e, is formed in the combustion-chamber, which causes the products of combustion to take a forward course l toward the front of the boiler, and thus a much greater section of the boiler is exposed to high heat.

I am aware that a fire-wall within the combustion-chamber acting as a deiector is not new. I therefore do not claim this feature independently, but only as forming a part of my invention, in combinationv with the other features herein named.

It will also be observed that when lthe tubes are so covered with fire-clay it is necessary'to feed the iire with air taken from behind, as well as from air introduced through the ashpit door, and that I provide a simple and eicient way of attaining this end.

It will also be observedthat the fire is therefore provided with air at the front and at the rear, and that therefore a uniform combustion of fuel is obtained.

Of course it is not essential that the tubes a be covered with nre-brick or fire-clay, in which case they would not form a barrier or wall across the combustion-chamber suicient to cause the entire products of combustion to be directed forward. The tubes and pipes should be so coupled together and to the boiler as to provide for their expansion and contraction.

Of course I may use in lieu of the tubes a metal rods for supporting the re brick or clay, in which case, of course, the object of this portion of the invention would be to form awall or barrier only in the combustion-chamber, for the purpose of throwing the heat to the forward end of the boiler.v

The pipe Amay have a blow-off passage and cock in it, if desired.

I deliver, by aid of the air-passage d, the air at the back of the grate, and the object is to force the burning upon the grate from the back toward the front, and by observing the IOC manner in which I arrange the parallel and inclined pipes a, and the object thereof, the special benefits of providing for the entry of the air herein shown will be obvious to all persons skilled in the construction and adaptation of steam-boilers and furnaces.

I am aware that tubes have been connected with a steam-boiler and carried through the furnace to heat the water, as in English patent to Mack, where the tubes or pipes are made in the form of an arch over the firebox and continued the entire length of the boiler. My construction, it will be observed, however, does not confine the fire and heat and compel it to go the length of the boiler under the tubes, which is found obj eetionable in practice. My arrangement presents the greatest heating-surface of pipes at the hottest part of the furnace, and not onlyleaves the flame and heat free to ascend to the shell of the boiler, but by presenting an inclined barrier to the heat and flame actually tends to greatly increase the effect of heat on the boiler itself. Thus I obtain the full benefit of the circulating steam-generating pipes, and a rapid circulation of the water in the boiler, and also cause a great saving of fuel, on account of the back of the furnace not being choked with pipes, thus obtainingfree circulation and an unobstructed draft. rllhis arrangement of tubes in connection with the furnace an d the air-duct enables the steam to be raised easier and safer, and with less fuel, than by any other arrangement of parts known to me.

Having thus fully described my invention, I claim and desire to secure by Letters Patent of the United States- 1. In combination with a steam-boiler and a furnace, the arrangement of pipes herein described, consisting of the side pipes, b-b, connecting with the opposite sides of the boiler near the front, and communicating with the interior of the same, the cross-pipe a', the parallel pipes a, protected with a suitable covering, e, thecross-pipe A, so placed in relation to the cross-pipe c that the parallel pipes a will incline toward the front of the boiler, and a pipe, b2, comnninicating with the interior of the boiler at the bottom and near the back end thereof, all adapted to induce a circulation of water within the boiler and within the said pipes, and to aid in the deiection of the fire and heat in the combustion-chamber to and against the shell of the boiler from the front tothe rear without obstructing the rear draftpassage under the boiler, substantially as and for the purposes set forth.

2. In the combustion-chamber of a furnace, the air-passage d, extending from the front to the back of the ash-pit, and adapted to deliver air at the back end of the grate-bars, and tov induce a draft from the back toward the front of the combustion-cllamber, an'd in combination with the pipes A a and the parallel inclined deflecting-pipes a, suitably connected with a steam-boiler, substantially as and for the purposes set forth.

XVM. U. FAIRBAIRN.

Vitnesses:

F. F. lirmronnd, XV. CLIFTON Foco. 

